Former Vice President Joe Biden’s campaign inadvertently sent out its post-debate fundraising email on Wednesday afternoon, hours before the Democrat candidates took stage in Atlanta, Georgia.

“I’m leaving the fifth Democratic debate now,” the former vice president wrote supporters. “I hope I made you proud out there and I hope I made it clear to the world why our campaign is so important.”

Biden proceeds in the rest of the email to highlight his “ability to reach across the aisle,” before ultimately ending with an appeal for political contributions for his campaign. Some members of the media, like Jess Bidgood of The Boston Globe, speculated that Biden’s appeal to bipartisanship in the email may indicate he plans to focus his attacks on Sen. Elizabeth Warren (D-MA) during Wednesday’s debate.

Warren, until the recent rise of South Bend Mayor Pete Buttigieg, has been seen as Biden’s biggest rival for the Democrat nomination. As such, the two have sparred openly over the direction of the Democrat Party.

Biden, who claims to be the only Democrat able to win back the white working class in 2020, is campaigning as something of a moderate who will bring forth incremental change. The strategy is evident in the former vice president’s policy platform, which is full of ideas that were seen as too radical during the Obama years but are now considered tepid when compared to those advocated by progressives like Sen. Bernie Sanders (I-VT) and Rep. Alexandria Ocasio-Cortez (D-NY).

Warren, on the other hand, is a proponent of radical change, as exhibited by her endorsements of a wealth tax and the Green New Deal.

The differences between the two have been evident in their recent back and forth on Medicare for All. Biden, who opposes the universal healthcare plan in favor of expanding the Affordable Care Act through a public option, has accused Warren and other supporters of Medicare for All of being dishonest. In particular, the former vice president has claimed Warren is lying about the true costs of Medicare for All and how she plans to fund the program.

“She’s making it up,” the former vice president told PBS News Hour earlier this month when asked about cost estimates Warren’s campaign had released on the proposal:

Look, nobody thinks it’s $20 trillion. It’s between 30 and $40 trillion. Every major independent study that’s gone out there, that’s taken a look at this, there is no way — even [Sen. Bernie Sanders (I-VT)], who talks about the need to raise middle-class taxes, he can’t even meet the cost of it.

Warren has responded to such attacks by suggesting Biden was “running in the wrong presidential primary.”